Until CorelDRAW X6, hitting the Ctrl-TAB would navigate between all open documents. For e.g. in CorelDRAW X6, if you open Document A followed by B, D & C, hitting Ctrl+TAB will navigate you through documents in same order i.e. A, B, D, C.  With CorelDRAW X7, the Ctrl+TAB navigation works slightly different. It now keeps a history of the last document that was accessed. This way, when you hit Ctrl+TAB key, it will always toggle between current document and last used document. Alternatively, if you want to toggle between all open documents you keep holding down the Ctrl key and hit TAB key to navigate between all open documents.

Tip provided by Pratik Shah, CorelDRAW Master, Graphic Designer & Trainer.